THISTLE FAMILY 959 



or glabrate, twice pinnatifid; primary segments more or less spreading, more or 

 less de(;urrent into the wing-margins; secondary segments short, lanceolate, flat, 

 spinulose-tipped; involucres 4-5 mm. high, 3-4 mm. broad; bracts lance-elliptic 

 or elliptic, obtnse, with brown (rarely nearly black) margins; ligules 2-3 mm. 

 long and broad. Shores, hillsides, and roadsides: Newf. — Va. — Colo. — B.C.; 

 nat. or adv. from Eu. Je-S. 



10. A. multiflora Hook. Stem 3-10 dm. high, villous; leaves linear, 5-10 

 cm. long, 5-8 mm. broad, somewhat pubescent or glabrate, pectinately cleft into 

 lanceolate, serrulate lobes; involucres 4-5 mm. high, 4-6 mm. broad; bracts 

 more or less villous, elliptic with brown margins; ligules 10-12, suborbicular, 

 1-1.5 mm. long. Valleys: Mack. — Sask. — Alaska. Boreal. Jl-Au. 



116. ANTHEMIS L. Corn Chamomile. 



Annual or perennial herbs. Leaves alternate, mostly pinnatifid or bipinnat- 

 ifid. Heads solitary at the ends of the branches, usually radiate. Involucre 

 saucer-shaped; bracts in about 3 series of nearly the same length, usually thin; 

 receptacle conic to hemispheric, chaffy; paleae membranous with a distinct mid- 

 rib. Raj'-flowers pistillate and fertile; ligules white. Disk-flowers herma- 

 phrodite and fertile; corollas yellow. Anthers with ovate obtuse tips. Style- 

 branches truncate and fimbriate at the apex. Achenes subcylindric or somewhat 

 obovoid, not angled, with filiform ribs. Pappus wanting, or a minute crowTi. 



1. A. arvensis L. A leafy annual; stem 2-5 dm. high, branched, hirsute- 

 villous; leaves 3-5 cm. long, bipinnatifid, with linear-lanceolate cuspidate lobes, 

 hirsute- villous; involucre 4-5 mm. high, 7-12 mm. broad; bracts villous-hirsute ; 

 receptacle conic; paleae linear-lanceolate, abruptly cuspidate; ligules white, 7-12 

 mm. long, 3-4 mm. wide; achenes subcylindric, 10-ribbed; pappus a minute 

 border. Field and waste places: Me. — Ga. — Ore. — B.C.; adv. or nat. from Eu. 



117. MARUTA Cass. May Weed, Dog Fennel, Dog Chamomile. 



Leafy annuals. Leaves alternate, bipinnatifid, with narrow divisions. 

 Heads radiate, soUtary at the ends of the branches. Involucre saucer-shaped; 

 bracts in 2 series, subequal. Receptacle conic, chaffy towards the apex; paleae 

 subulate, stiff, rather persistent. Ray-flowers 10-15, neutral; ligules white. 

 Disk-flowers hermaphrodite and fertile; corolla-tube cylindric, longer than the 

 funnelform throat; lobes 5, ovate, spreading. Anthers with ovate obtuse tips. 

 Style included, with short branches truncate and fimbriate at the apex. Achenes 

 nearly cylindric, 10-ribbed, glandular-tubercled. Pappus wanting. 



1. M. Cotula (L.) DC. Annual, with fetid odor; stem glabrous or slightly 

 pubescent above, 3-6 dm. high; leaves 3-5 cm. long, twice or thrice pinnatifid, 

 with narrow hnear-filiform divisions; glabrate or somewhat hairy; involucre 

 8-12 mm. broad; bracts oblong, obtuse, somewhat pubescent; ligules 10-18, 

 white, about 1 cm. long, at length reflexed. Anlhemis Co'ula L. Fields and 

 waste places: Newf. — Fla. — Calif. — B.C. — Yukon; nat. from Eu. Plain — Sub- 

 mont. Jl-S. 



118. CHAMOMILLA (Hall.) Gilib. Chamomile, Pineapple-weed, 



Green Dog-fennel. 



Mostly annual glabrous herbs. Leaves alternate, once to thrice pinnatifid 

 into narrow divisions. Heads solitary or corymbose, radiate or discoid. Invo- 

 lucre saucer-shaped to hemispheric ; bracts in 2-4 series, somewhat imbricate, ob- 

 tuse, scarious-margined; receptacle conic, hemispheric, or subglobose, naked. 

 Ray-flowers, if present, pistillate and fertile; ligules white. Disk-flowers numer- 

 ous, hermaphrodite and fertile; corollas yellow; anthers with ovate obtuse tips; 

 style-branches short, with truncate tips. Achenes usually asymmetric, with 3-5 

 ribs on the inner half, the back being nerveless. Pappus of a more or less de- 

 veloped crown or margin. [Matricaria L., in part.] 



1. C. suaveolens (Pursh) Rydb. Annual; stem glabrous, verv leafy, much 

 branched, 1-4 dm. high; leaves glabrous, 2 or 3 times pinnatifid, v\ith linear acute 



